You can access your closed reviews from your Reviews tab. Under Archived, you'll see your most recent closed reviews and you can click Show x more to access the rest.
If you're a manager and need to see a team member's closed reviews, you can go to your Team tab and click on the person's name. Once on their profile, go to their Reviews tab and look under Archived as above.
If you're an admin/moderator and need to view someone's closed reviews, you can search for their name in the search bar and then follow the same steps as above once on their profile.